diff options
| author | David Howells <dhowells@redhat.com> | 2006-01-06 00:11:44 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-01-06 08:33:33 -0800 |
| commit | 7ee1dd3fee22f15728f545d266403fc977e1eb99 (patch) | |
| tree | e2f9f42b0731d5006fa329a590069be6787af1de | |
| parent | 5c40f7f373889930d176a515ec375b60a70b5b49 (diff) | |
[PATCH] FRV: Make futex code compilable on nommu [try #2]
Make the futex code compilable and usable on NOMMU by making the attempt to
handle page faults conditional on CONFIG_MMU. If this is not enabled, then
we can assume that EFAULT returned from futex_atomic_op_inuser() is not
recoverable, and that the address lies outside of valid memory.
handle_mm_fault() is made to BUG if called on NOMMU without attempting to
invoke the actual handler (__handle_mm_fault).
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
| -rw-r--r-- | include/linux/mm.h | 22 | ||||
| -rw-r--r-- | kernel/futex.c | 7 |
2 files changed, 26 insertions, 3 deletions
diff --git a/include/linux/mm.h b/include/linux/mm.h index 26f3094911a5..bc01fff3aa01 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -717,12 +717,28 @@ extern int vmtruncate(struct inode * inode, loff_t offset); extern int vmtruncate_range(struct inode * inode, loff_t offset, loff_t end); extern int install_page(struct mm_struct *mm, struct vm_area_struct *vma, unsigned long addr, struct page *page, pgprot_t prot); extern int install_file_pte(struct mm_struct *mm, struct vm_area_struct *vma, unsigned long addr, unsigned long pgoff, pgprot_t prot); -extern int __handle_mm_fault(struct mm_struct *mm,struct vm_area_struct *vma, unsigned long address, int write_access); -static inline int handle_mm_fault(struct mm_struct *mm, struct vm_area_struct *vma, unsigned long address, int write_access) +#ifdef CONFIG_MMU +extern int __handle_mm_fault(struct mm_struct *mm,struct vm_area_struct *vma, + unsigned long address, int write_access); + +static inline int handle_mm_fault(struct mm_struct *mm, + struct vm_area_struct *vma, unsigned long address, + int write_access) { - return __handle_mm_fault(mm, vma, address, write_access) & (~VM_FAULT_WRITE); + return __handle_mm_fault(mm, vma, address, write_access) & + (~VM_FAULT_WRITE); } +#else +static inline int handle_mm_fault(struct mm_struct *mm, + struct vm_area_struct *vma, unsigned long address, + int write_access) +{ + /* should never happen if there's no MMU */ + BUG(); + return VM_FAULT_SIGBUS; +} +#endif extern int make_pages_present(unsigned long addr, unsigned long end); extern int access_process_vm(struct task_struct *tsk, unsigned long addr, void *buf, int len, int write); diff --git a/kernel/futex.c b/kernel/futex.c index 5e71a6bf6f6b..5efa2f978032 100644 --- a/kernel/futex.c +++ b/kernel/futex.c @@ -356,6 +356,13 @@ retry: if (bh1 != bh2) spin_unlock(&bh2->lock); +#ifndef CONFIG_MMU + /* we don't get EFAULT from MMU faults if we don't have an MMU, + * but we might get them from range checking */ + ret = op_ret; + goto out; +#endif + if (unlikely(op_ret != -EFAULT)) { ret = op_ret; goto out; |